(1-3)(1-6)-β-glucan-enriched materials from Lentinus edodes mushroom as a high-fibre and low-calorie flour substitute for baked foods

BACKGROUND: Extensive physiological and biological emphasis has been placed on pharmaceutical and medicinal uses of mushrooms containing β‐glucans, but their incorporation into processed functional foods is quite limited. Thus, low‐grade Lentinus edodes mushrooms were utilised to produce β‐glucan‐enriched materials (BGEMs), which were evaluated as a high‐fibre and low‐calorie substitute for wheat flour. RESULTS: The fractions obtained from Lentinus edodes mushrooms contained 514 g kg^?1 of (1–3)‐β‐glucans with (1–6)‐β‐linked side chains and the chemical structure was confirmed by ¹³C NMR and FTIR spectroscopy. Replacement of a portion of the wheat flour with BGEMs resulted in the solutions with lower values of pasting parameters and also caused significant changes in starch gelatinisation. When BGEMs were incorporated into cake formulations, batter viscosity increased with more shear‐thinning behaviours and elastic properties improved. Overall, the cakes containing more BGEMs showed decreased volume and increased hardness while no significant differences were observed between the control and BGEM cakes containing 1 g of β‐glucan per serving. CONCLUSION: As a wheat flour substitute, the BGEMs that were prepared from low‐grade Lentinus edodes mushrooms, could be successfully used to produce cakes containing 1 g of β‐glucan per serving with quality attributes similar to those of the control. Copyright © 2011 Society of Chemical Industry     

Edible mushrooms as producers of amylases

Five varieties of mushroom—Absidia blakesleeana, Agaricus bisporus, Lentinus edodes, Peziza auburouniv and Polyporus sulphureus—were qualitatively examined for their ability to hydrolyse starch. Quantitative estimation was made to compare the amylolytic activity of the five types of mushroom propagated on a synthetic medium with that of Aspergillus niger NRRL 337.Lentinus edodes proved to be the most promising strain for amylase production. The amylolytic activity of Lentinus edodes reached its maximum (621 U/ml) after seven days of incubation, the dry mycelium yield being 7·5 g/l with a protein content of 34%.Lentinus edodes was then propagated on various extracts of food wastes—malt sprouts, navel orange peel, potato peel, rice bran, corn steeping water and rice steeping water. Malt sprouts extract proved to be a promising medium for Lentinus edodes propagation as well as for amylase production.     

Non-Volatile Taste Components of Different Cultivated Mushrooms at Mycelia,Primordium, and Fruit Body Cultivation Stages

Free amino acid, flavor 5’-nucleotides, organic acid, and the values of equivalent umami concentration of cultivable mushrooms, namely Pleurotus eryngii, Agrocybe aegerita, and Lentinus edodes, were investigated at different cultivation stages, mycelia, primordium, and fruit bodies. Fruit bodies were higher than mycelia in contents of total free amino acid, flavor 5’-nucleotides, and the values of equivalent umami concentration in three cultivated mushrooms, but lower in contents of total organic acid in P. eryngii and L. edodes, respectively. Contents of total organic acid at three cultivation stages of three cultivated mushrooms ranged from 32.65 to 125.50 mg g^–1 with the primordium stage of L. edodes being the highest. Overall, the amount of the nutrition and flavor components of mushroom might be related with mushroom species, fermentation way, and cultivated time. Some compounds could be also extracted from mycelia or primordium of mushrooms other than fruit body.     

乳酸菌发酵香菇对肠道菌群的调节作用及其产品研制

将香菇经乳酸菌发酵后,通过小鼠灌胃实验和16S rRNA高通量测序,研究其对肠道菌群结构和多样性的影响,并研制调味即食产品。结果表明,中等剂量（10 g/kg,以小鼠质量计）的发酵香菇改变了小鼠肠道菌群的物种多样性,其特有物种和稀有物种数量增加,且个体差异减小,物种分布更均匀。发酵香菇可不同程度地增加小鼠肠道内有益菌群,如Muribaculaceae、乳杆菌属（Lactobacillus）、Dubosiella、Lachnospiraceae等的定殖,降低螺杆菌属（Helicobacter）、支原体（Mycoplasma）等致病菌的相对丰度,从而改善肠道健康。通过单因素和响应面优化实验,获得乳酸菌发酵香菇调味即食产品的最佳配方为：发酵香菇块81.5%、甜面酱1.0%、豆瓣酱1.5%、白砂糖6.0%、藤椒油3.0%、芝麻2.0%、辣椒油4.0%、姜汁1.0%（均为质量分数）。为乳酸菌发酵技术在香菇深加工中的应用提供了有益参考。     

Cultivation of the shiitake mushroom (Lentinus edodes) on lignocellulosic waste

The Shiitake mushroom (Lentinus edodes) was successfully grown and fruited on a substrate containing 7 parts hardwood sawdust and 3 parts oatmeal. Colonised blocks of substrate placed in a fruiting environment produced edible mushrooms in 9–15 days with an average total yield of c. 135% fresh weight mushrooms per unit dry weight of substrate. The mushroom fruited when daily temperatures ranged between 11 and 26°C.     

Effect of ultraviolet‐B irradiation on antioxidative properties of aqueous extracts from shiitake (Lentinus edodes) mushrooms

Antioxidant properties of aqueous extracts from Lentinus edodes treated with UV‐B irradiation were examined in vitro systems including DPPH, ABTS and oxygen radical absorbance capacity (ORAC) assays and in riboflavin‐photosensitised oil‐in‐water (O/W) emulsions. Changes in total phenolics, total flavonoids and vitamin C were also analysed. Lentinus edodes receiving 25 kJ m^?2 UV‐B treatment showed high radical scavenging ability based on DPPH and ABTS assays compared with samples with 0, 50 and 75 kJ m^?2, while those with 50 kJ m^?2 had higher antioxidant capacities than other samples from ORAC assays. Samples with 25 kJ m^?2 UV treatment had significantly 7.1% higher total phenolic content, 12.0% higher total flavonoid content and 8.0% higher vitamin C content than UV‐B‐untreated sample (P < 0.05), respectively. In O/W emulsions under riboflavin photosensitisation, 25 and 50 kJ m^?2 UV treatment significantly increased the oxidative stability compared with other samples based on headspace oxygen content and lipid hydroperoxide analyses (P < 0.05). Aqueous extracts of UV‐B‐treated mushrooms possessed enhanced antioxidant properties compared with untreated mushrooms.     

Effects of Tween 80 on the liquid fermentation of <Emphasis Type="Italic">Lentinus edodes</Emphasis>

This paper explored the effects of Tween 80 on the biomass, intracellular polysaccharide (IPS) content, fermentation parameters, the pellets size of mycelium, and the antioxidant activity of IPS in Lentinus edodes liquid fermentation. With adding to Tween 80, the outputs of biomass and IPS increased during the L. edodes fermentation, respectively, while the reducing sugar content was decreased, as well as, the time courses of pH value were different. It was also shown that the addition of Tween 80 could protect the intact of pellets from breaking down. The effects of Tween 80 on the main structure of IPS were no obvious, and the IPS were revealed similar infrared spectrum, as was indicated by the infrared spectrum analysis. Improvements in the scavenging capacity of DPPH radicals of IPS were observed in Tween 80 treated group compared with the control group. Tween 80 exerts impacts on the liquid fermentation of L. edodes.     

Amino acid composition of wheat milling by-products after bioconversion by edible fungi mycelia

The bioconversion and nutritional upgrading of soft wheat bran and shorts by the white-rot fungi Lentinus edodes and Pleurotus ostreatus were studied. The amino acid profiles of the milling by-products, before and during mycelial colonization over a period of three weeks, were determined. Quantitative and qualitative changes in the amino acid composition of the bioconversion products were estimated. Mycelial colonization, while increasing the protein content of the substrates, did not affect the balance of amino acids that remained basically unmodified, except for a prevalent increment in the relative contents of tyrosine, arginine and lysine to a lesser degree.     

Effects of γ-irradiation on the flavour of dry shiitake (lentinus edodes sing)

Dry shiitake (Lentinus edodes Sing) was irradiated with doses of 5 and 10 kGy using ⁶⁰Co. The total volatile compounds were decreased by more than 50%. Irradiation increased the concentrations of some minor volatile compounds, such as 3-methyl-2-butanol and I-hexanol. However, the major flavour compounds including eight-carbon and sulphur-containing compounds were significantly reduced. The ratio of the eight-carbon compounds, such as 3-octanone, 3-octanol and 1-octen-3-ol, to total volatiles decreased from 72% in the control to 21% in the 10 kGy irradiated samples. The unidentified compounds which may have been formed by decomposition or polymerization following irradiation of precursors need to be studied in greater depth.     

The effect of superfine grinding on physicochemical properties of three kinds of mushroom powder

The effects of superfine grinding on apparent structure, physicochemical properties, and functional characteristics of three kinds of mushroom (Lentinus edodes, Hericium erinaceus, and Cordyceps militaris) powders were investigated. Coarse and 100-mesh powders of the mushrooms were prepared by common grinding, while a superfine powder was obtained by superfine grinding. By comparing the mushrooms before and after grinding, it was found that the mushroom fines did not produce new chemical groups but increased crystallinity. The results of the physicochemical properties revealed that the fines became less fluid after grinding. The protein content and solubility increased as the particle size decreased. The water and oil holding capacity, glucose binding capacity, cation exchange capacity, and antioxidant activity of the mushroom fines increased after grinding. This study provides a theoretical basis for the development process of edible mushroom food, as well as new ideas for the development of edible mushrooms.     

ANTIOXIDANT PROPERTIES OF LENTINUS EDODES AND AGARICUS BLAZEI EXTRACTS

ABSTRACT

This work aimed to evaluate the antioxidant activity of Lentinus edodes and Agaricus blazei mushrooms, as well as to measure the content of total phenolic compounds of mushroom extracts and verify the oxidative stability of soybean oil added with mushroom extracts that showed higher antioxidant activity according to the methods of the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH^•) free radical scavenging and the β‐carotene/linoleic acid system. According to the DPPH^• method, the maximum antioxidant activity for L. edodes and A. blazei methanol extracts was 92.84 and 95.10%, respectively. For the β‐carotene/linoleic acid system, the highest values of antioxidant activity were 93.06% for L. edodes and 78.96% for A. blazei. The content of total phenolic compounds ranged from 7.21 to 128.44 and 26.67 to 134.67 mg gallic acid equivalent/g for L. edodes and A. blazei, respectively. The oxidative stability values provided by the Rancimat method indicated that the two varieties presented similar induction period of 19.85 h.

PRACTICAL APPLICATIONS

Mushrooms present high content of antioxidant compounds that are capable of reducing the harmful effects of free radicals. Among the antioxidants present in mushrooms, phenolic compounds stand out as phenolic acids, flavonoids and tocopherols. To decrease or prevent lipid oxidation, synthetic antioxidants are used as food additives. Nevertheless, studies have revealed that these compounds are likely to pose risks to human health. The concern regarding the safety of synthetic antioxidants has motivated the search of natural antioxidants that can substitute them totally or partially.

     

Advances in lentinan: Isolation,structure, chain conformation and bioactivities

Lentinan, a β-(1 → 3)-d-glucan isolated from a common edible mushroom, Lentinus edodes, is known as a biologically active macromolecules with very strong host-mediated anti-cancer activity, via activation of the human immune system. However, its widespread medicinal application is hindered by some technical difficulties in its extraction and purification, as well as a lack of thorough understanding of the structure-and-function relationship of this polysaccharide. This review aims at highlighting the different areas of research conducted on lentinan in the past 40 years, including its extraction and purification processes, the analysis of structure, the determination of its chain conformation and conformation transition in solution, as well as its rheological properties and bioactivities especially on anti-cancer treatment. About 156 literatures were cited to summarize the advancement of lentinan in the review paper.     

Compositional and nutritional studies on edible wild mushroom from northeast India

Two species of mushrooms Schizophyllum commune and Lentinus edodes from Northeast India were assessed for their nutritive value. Protein contents of S. commune (16%) and L. edodes (23%) were high, but fat content was low (2%) in both the mushrooms. Oleic and linoleic acids accounted for 72–77% of the total fat in both the mushrooms. Essential amino acid contents of S. commune and L. edodes were 34% and 39%, respectively. The chemical scores of S. commune (28) and L. edodes (29) were low compared to whole egg protein. Methionine was the limiting amino acid in both the mushrooms. Protein quality evaluation by NPR (net protein ratio), NPU (net protein utilization) and TDP (true digestibility of protein), showed that the mushrooms were comparatively much lower then casein in all the parameters examined. Animals on L. edodes showed significantly (p < 0.05) higher NPR, RNPR, and NPU than animals on the S. commune diet. True protein digestibility of the L. edodes diet was also significantly (p < 0.05) higher than the S. commune diet.     

Radical scavenging activities,endogenous oxidative enzymes and total phenols in edible mushrooms commonly consumed in Europe

Edible mushrooms are a good source of antioxidants. Methanol extracts of mushrooms such as Pleurotus sp., Agaricus bisporus, Morchella esculenta, Boletus edulis (approx. 2 mg mL^?1) showed a high 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging activity close to 90%. Water extracts showed even higher antioxidant activity. In this case, B. edulis, Lentinus edodes and Amanita cesarea showed the highest 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) scavenging activity at approx. 0.14 mg mL^?1. Other mushrooms such as Lactarius deliciosus and Cantharellus cibarius showed lower antioxidant activity in both extracts. Oxidative enzymes (peroxidases and polyphenol oxidases) present in the water fractions reduced their antioxidant activity by different extents since the phenols responsible for the antioxidant activity were not only those substrates of the oxidative enzymes. Other phenolic compounds and low‐molecular‐weight compounds were also involved in the antioxidant activity and differed depending on mushroom species. Copyright © 2007 Society of Chemical Industry     

Drying kinetics of whole and sliced <Emphasis Type="Italic">shiitake</Emphasis> mushrooms (<Emphasis Type="Italic">Lentinus edodes</Emphasis>)

Isotherms of shiitake mushroom (Lentinus edodes) at 25 and 40°C were determined and drying kinetics of whole and sliced shiitake mushrooms were tested using a convective air drying method at different drying temperature of 40, 50, 60, and 70°C. The monolayer moisture contents of the mushroom were 7.23 and 5.44 g water/100 g of dry solids at 25 and 40°C, respectively. Both mushroom samples showed falling drying rate periods with increasing drying rates with increases in drying temperature, and the drying rate of the sliced mushrooms was faster than that of the whole mushrooms at the same drying conditions. The kinetic parameters for dehydration of the mushrooms were determined using the Newton model and the Classical diffusion model. Activation energy (E _a ) values as determined using the Newton model were 22.58 and 20.48 kJ/mol for the whole and sliced mushrooms, respectively.     

PHYSIOLOGICAL ACTIVITIES OF CHUNGKOOKJANG (KOREAN TRADITIONAL SOYBEAN PASTE) PILL AS A FUNCTIONAL FOOD

Chungkookjang, Chungkookjang pill and mushroom (Lentinus edodes) had fibrinolytic activities. The mushroom had a higher level of fibrinolytic activity (15.1 unit/mg) than Chungkookjang pill (10.0 unit/mg) and Chungkookjang (0.6 unit/mg) in spite of heat treatment. Hot‐water extracts of Chungkookjang and Chungkookjang pill showed slightly higher macrophage‐stimulating activities than the positive control, lipopolysaccharide. Also, Chungkookjang pill (3.58 µg/g) had lower cyclo‐His‐Pro content than Chungkookjang (26.5 µg/g). In addition, Chungkookjang pill had less content of flavor components than Chungkookjang and, especially, the 2,5‐dimethylpyrazine content of Chungkookjang pill was less than that of Chungkookjang. When comparing with Chungkookjang, Chungkookjang pill had similar physiological activities and more palatable flavor.     

In vitro antioxidative and antimutagenic activities of oak mushroom (Lentinus edodes) and king oyster mushroom (Pleurotus eryngii) byproducts

The in vitro antioxidative and antimutagenic activities of ethanolic extracts from oak mushroom (Lentinus edodes) and king oyster mushroom (Pleurotus eryngii) byproducts were investigated. The antioxidant capacity of the extracts was assessed by determining the ferricyanide reducing power, scavenging activity on nitrite, DPPH radical, superoxide anions and hydroxyl radicals, ferrous ion chelating ability, and inhibitory effect on linoleic acid peroxidation and xanthine oxidase. The antimutagenic activity, on the other hand, was based on the suppression of mitomycin C-induced mutagenesis in Escherichia coli cells. Both the mushroom extracts showed strong antioxidative and antimutagenic effects at higher concentrations. In general, extracts from the oak mushroom byproduct had greater antioxidative and antimutagenic abilities than that of the king oyster extract. Results of this study demonstrate that the mushroom byproducts possess strong antioxidant capacity in vitro and may be useful as a functional biomaterial in the preparation of health-promoting food products and animal feeds.     

Lentinus edodes heterogalactan: Antinociceptive and anti-inflammatory effects

Cold aqueous extraction of basidiocarps (fruiting bodies) of the edible mushroom Lentinus edodes (shiitake) gave rise to a heteropolysaccharide, whose chemical structure, antinociceptive and anti-inflammatory properties were determined. Its chemical structure was based on monosaccharide composition, methylation analysis, and NMR spectroscopy (¹H, ¹³C, HSQC, HSQC-TOCSY, HSQC-NOESY, and coupled HMQC). It was found to be a fucomannogalactan with a main chain of (1 → 6)-linked α-d-galactopyranosyl units, partially substituted at O-2 by single-unit β-d-Manp or α-l-Fucp side chains. The polysaccharide produced a marked and dose-related effect when assessed against acetic acid-induced visceral nociception. Prevention of peritoneal capillary permeability and leukocyte infiltration caused by the acetic acid was similar in potency and effectiveness.     

Effects of irradiation and drying on volatile components of fresh shiitake (Lentinus edodesSing)

Fresh shiitake (Lentinus edodes Sing) was irradiated with doses of 0·5, 1 and 2 kGy using ⁶⁰Co. Effects of γ-irradiation and drying on the volatile composition of shiitake were studied by gas chromatography (GC) and GC–mass spectrometry. Irradiation above 1·0 kGy could inhibit the growth and mould decay of fresh shiitakes after harvesting. Irradiation with 2 kGy increased the eight-carbon volatile components of fresh shiitake. Treatment at 1 kGy irradiation of fresh shiitake produced some new volatile compounds in the dry product, such as methylethyl disulphide, sulphinylbis methane, methyl(methylthio)ethyl disulphide and N-(3-methylbutyl) acetamide. The eight-carbon compounds mostly disappeared after drying. The amount of sulphur-containing volatile compounds in dried shiitake became lower during irradiation. Irradiation with doses of 1 or 2 kGy of fresh shiitake did not increase the volatile content of shiitake after drying. © 1998 SCI.     

Market Survey and Risk Assessment for Trace Metals in Edible Fungi and the Substrate Role in Accumulation of Heavy Metals

Levels of cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), iron (Fe), and zinc (Zn) were investigated in 285 samples of 9 species of edible fungi (Lentinus edodes, Auricularia auricula, Pleurotus ostreatus, Tremella fuciformis, Flammulina velutipes, Agrocybe chaxinggu, Armillaria mellea, Agaricus bisporus, and Pholiota nameko), which were collected from markets in Beijing, China. In addition, edible fungi and culture substrates were collected from 7 cultivation bases to examine the role of the substrate in trace metal accumulation. Trace metal concentrations were determined on a dry weight basis. Data showed that all the edible fungi contained trace metals, the levels of which varied among species, and there were significant positive correlations between trace metal (Cd, Pb, and As) concentrations in mushrooms and their substrates. The concentrations of Cd, As, Hg, Pb, Fe, and Zn in the tested fungi ranged from 0.005 to 13.8 mg/kg, nd to 1.62 mg/kg, nd to 0.506 mg/kg, 0.011 to 22.1 mg/kg, 46.3 to 2514 mg/kg, and 14.6 to 289 mg/kg, respectively. In general, concentrations of Cd, As, Hg, Pb, Fe, and Zn were relatively high in L. edodes, whereas Tremella fuciformis and P. nameko had relatively low levels of trace metals. Furthermore, the estimated weekly intake of trace metals was calculated and compared with the WHO/FAO provisional tolerable weekly intake. The estimated weekly intake of Cd, As, Hg, Pb, Fe, and Zn from consuming edible fungi was lower than the provisional tolerable weekly intake.